AG VLSI Design and Architecture

SFB 501 - Project D1: Application System "Buildings"

PSiGene Pattern Catalog

Intent

A thermal junction is used for separate two thermal masses that exchange heat. This pattern calculates the heat-flow between these masses.

Also Known As

Simulation thermischer Verbindung [Rie96] ( http://wwwagz.informatik.uni-kl.de/projects/SFB501/D1/PSiGene/publications.shtml#Rie96.0 ).

Motivation

The simplest case of separating two rooms is a wall. On different temperatures in each of the room a heat-flow exists between these rooms through the wall which is depending on the thermal resistance of that wall and on the difference on temperature of the rooms.

Applicability

With every thermal junction. The junction`s area and the heat resistance have to be known or calculable.

Structure

A thermal junction connects two thermal masses. Depending on the difference of temperature between these masses a heat-flow exists.

This pattern serves two functionalities: first, calculating the actual heat-flow, and second, returning it with correct sign to the caller.

Participants

Collaborations

A thermal junction always connects two thermal masses. If a mass has connections to multiple other masses, each neighborhood has to be modelled separately.

Consequences

To apply this pattern the heat resistance of the junction has to be known or calculable.

Implementation

    ^self {neighbouringObject} instance {getTemperature}

    ^self {thermalResistance}
        + self {neighbouringObject} instance
                {getThermalResistance}

    | deltaTemperature |
    deltaTemperature :=
        self {getTemperature} - anObject {getTemperature}.
    ^(deltaTemperature * self {area})
        / (self {getThermalResistance}
            + (anObject {thermalResistance} / 2))

Related Patterns

ThermalMass , ThermalExchange .

PEdit description

Pattern ThermalJunction Category simulation
    ObjectType use target
    SingleRelation use neighbouringObject
    Attribute use area
    Attribute use thermalResistance
    SingleMethod implement getTemperature
    SingleMethod implement getThermalResistance
    SingleMethod implement getHeatFlowFor
End